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We produce 1000 realizations of synthetic clustering catalogues for each type of the tracers used for the baryon acoustic oscillation and redshift space distortion analysis of the Sloan Digital Sky Surveys- iv extended Baryon Oscillation Spectroscopic Survey final data release (eBOSS DR16), covering the redshift range from 0.6 to 2.2, to provide reliable estimates of covariance matrices and test the robustness of the analysis pipeline with respect to observational systematics. By extending the Zel'dovich approximation density field with an effective tracer bias model calibrated with the clustering measurements from the observational data, we accurately reproduce the two- and three-point clustering statistics of the eBOSS DR16 tracers, including their cross-correlations in redshift space with very low computational costs. In addition, we include the gravitational evolution of structures and sample selection biases at different redshifts, as well as various photometric and spectroscopic systematic effects. The agreements on the auto-clustering statistics between the data and mocks are generally within |$1\, \sigma$| variances inferred from the mocks, for scales down to a few |$h^{-1}\, {\rm Mpc}$| in configuration space, and up to |$0.3\, h\, {\rm Mpc}^{-1}$| in Fourier space. For the cross correlations between different tracers, the same level of consistency presents in configuration space, while there are only discrepancies in Fourier space for scales above |$0.15\, h\, {\rm Mpc}^{-1}$|⁠. The accurate reproduction of the data clustering statistics permits reliable covariances for multi-tracer analysis. [ABSTRACT FROM AUTHOR]

We present the cosmological analysis of the configuration-space anisotropic clustering in the completed Sloan Digital Sky Survey IV extended Baryon Oscillation Spectroscopic Survey (eBOSS) Data Release 16 galaxy sample. This sample consists of luminous red galaxies (LRGs) spanning the redshift range 0.6 < |$z$| < 1, at an effective redshift of |$z$| eff  = 0.698. It combines 174 816 eBOSS and 202 642 BOSS LRGs. We extract and model the baryon acoustic oscillation (BAO) and redshift-space distortion (RSD) features from the galaxy two-point correlation function to infer geometrical and dynamical cosmological constraints. The adopted methodology is extensively tested on a set of realistic simulations. The correlations between the inferred parameters from the BAO and full-shape correlation function analyses are estimated. This allows us to derive joint constraints on the three cosmological parameter combinations: D M(⁠|$z$|⁠)/ r d, D H(⁠|$z$|⁠)/ r d, and f σ8(⁠|$z$|⁠), where D M is the comoving angular diameter distance, D H is the Hubble distance, r d is the comoving BAO scale, f is the linear growth rate of structure, and σ8 is the amplitude of linear matter perturbations. After combining the results with those from the parallel power spectrum analysis of Gil-Marin et al. we obtain the constraints: D M/ r d = 17.65 ± 0.30, D H/ r d = 19.77 ± 0.47, and f σ8 = 0.473 ± 0.044. These measurements are consistent with a flat Lambda cold dark matter model with standard gravity. [ABSTRACT FROM AUTHOR]

We present the anisotropic clustering of emission-line galaxies (ELGs) from the Sloan Digital Sky Survey IV (SDSS-IV) extended Baryon Oscillation Spectroscopic Survey (eBOSS) Data Release 16 (DR16). Our sample is composed of 173 736 ELGs covering an area of 1170 deg2 over the redshift range 0.6 ≤ z ≤ 1.1. We use the convolution Lagrangian perturbation theory in addition to the Gaussian streaming redshift space distortions to model the Legendre multipoles of the anisotropic correlation function. We show that the eBOSS ELG correlation function measurement is affected by the contribution of a radial integral constraint that needs to be modelled to avoid biased results. To mitigate the effect from unknown angular systematics, we adopt a modified correlation function estimator that cancels out the angular modes from the clustering. At the effective redshift, z eff = 0.85, including statistical and systematical uncertainties, we measure the linear growth rate of structure f σ8(z eff) = 0.35 ± 0.10, the Hubble distance |$D_ H(z_{\rm eff})/r_{\rm drag} = 19.1^{+1.9}_{-2.1}$|⁠ , and the comoving angular diameter distance DM (z eff)/ r drag = 19.9 ± 1.0. These results are in agreement with the Fourier space analysis, leading to consensus values of: f σ8(z eff) = 0.315 ± 0.095, |$D_H(z_{\rm eff})/r_{\rm drag} = 19.6^{+2.2}_{-2.1}$|⁠ , and DM (z eff)/ r drag = 19.5 ± 1.0, consistent with ΛCDM model predictions with Planck parameters. [ABSTRACT FROM AUTHOR]

We analyse the clustering of the Sloan Digital Sky Survey IV extended Baryon Oscillation Spectroscopic Survey Data Release 16 luminous red galaxy sample (DR16 eBOSS LRG) in combination with the high redshift tail of the Sloan Digital Sky Survey III Baryon Oscillation Spectroscopic Survey Data Release 12 (DR12 BOSS CMASS). We measure the redshift space distortions (RSD) and also extract the longitudinal and transverse baryonic acoustic oscillation (BAO) scale from the anisotropic power spectrum signal inferred from 377 458 galaxies between redshifts 0.6 and 1.0, with the effective redshift of z eff = 0.698 and effective comoving volume of |$2.72\, {\rm Gpc}^3$|⁠. After applying reconstruction, we measure the BAO scale and infer D H(z eff)/ r drag = 19.30 ± 0.56 and D M(z eff)/ r drag = 17.86 ± 0.37. When we perform an RSD analysis on the pre-reconstructed catalogue on the monopole, quadrupole, and hexadecapole we find, D H(z eff)/ r drag = 20.18 ± 0.78, D M(z eff)/ r drag = 17.49 ± 0.52 and fσ 8(z eff) = 0.454 ± 0.046. We combine both sets of results along with the measurements in configuration space and report the following consensus values: D H(z eff)/ r drag = 19.77 ± 0.47, D M(z eff)/ r drag = 17.65 ± 0.30 and fσ 8(z eff) = 0.473 ± 0.044, which are in full agreement with the standard ΛCDM and GR predictions. These results represent the most precise measurements within the redshift range 0.6 ≤ z ≤ 1.0 and are the culmination of more than 8 yr of SDSS observations. [ABSTRACT FROM AUTHOR]

The completed extended Baryon Oscillation Spectroscopic Survey (eBOSS) catalogues contain redshifts of 344 080 quasars at 0.8 < z < 2.2, 174 816 luminous red galaxies between 0.6 < z < 1.0, and 173 736 emission-line galaxies over 0.6 < z < 1.1 in order to constrain the expansion history of the Universe and the growth rate of structure through clustering measurements. Mechanical limitations of the fibre-fed spectrograph on the Sloan telescope prevent two fibres being placed closer than 62 arcsec in a single pass of the instrument. These 'fibre collisions' strongly correlate with the intrinsic clustering of targets and can bias measurements of the two-point correlation function resulting in a systematic error on the inferred values of the cosmological parameters. We combine the new techniques of pairwise-inverse probability and the angular upweighting (PIP+ANG) to correct the clustering measurements for the effect of fibre collisions. Using mock catalogues, we show that our corrections provide unbiased measurements, within data precision, of both the projected |$\rm {\mathit{ w}_p}\left(\mathit{ r}_p\right)$| and the redshift-space multipole ξ(ℓ = 0, 2, 4)(s) correlation functions down to |$0.1\, h^{-1}{\rm Mpc}$|⁠ , regardless of the tracer type. We apply the corrections to the eBOSS DR16 catalogues. We find that, on scales |$s\gtrsim 20\, h^{-1}{\rm Mpc}$| for ξℓ, as used to make baryon acoustic oscillation and large-scale redshift-space distortion measurements, approximate methods such as nearest-neighbour upweighting are sufficiently accurate given the statistical errors of the data. Using the PIP method, for the first time for a spectroscopic program of the Sloan Digital Sky Survey, we are able to successfully access the one-halo term in the clustering measurements down to |$\sim 0.1\, h^{-1}{\rm Mpc}$| scales. Our results will therefore allow studies that use the small-scale clustering to strengthen the constraints on both cosmological parameters and the halo occupation distribution models. [ABSTRACT FROM AUTHOR]

Star-forming galaxies with strong nebular and collisional emission lines are privileged target galaxies in forthcoming cosmological large galaxy redshift surveys. We use the COSMOS2015 photometric catalogue to model galaxy spectral energy distributions and emission-line fluxes. We adopt an empirical but physically motivated model that uses information from the best-fitting spectral energy distribution of stellar continuum to each galaxy. The emission-line flux model is calibrated and validated against direct flux measurements in subsets of galaxies that have 3D-HST or zCOSMOS-Bright spectra. We take a particular care in modelling dust attenuation such that our model can explain both Hα and [O  ii ] observed fluxes at different redshifts. We find that a simple solution to this is to introduce a redshift evolution in the dust attenuation fraction parameter, f  = E star(B − V)/ E gas(B − V), as f (z) = 0.44 + 0.2 z. From this catalogue, we derive the Hα and [O  ii ] luminosity functions up to redshifts of about 2.5 after carefully accounting for emission line flux and redshift errors. This allows us to make predictions for Hα and [O  ii ] galaxy number counts in next-generation cosmological redshift surveys. Our modelled emission lines and spectra in the COSMOS2015 catalogue shall be useful to study the target selection for planned next-generation galaxy redshift surveys and we make them publicly available as 'EL-COSMOS' on the ASPIC data base. [ABSTRACT FROM AUTHOR]

In this paper we present a large data base of weak lensing light cones constructed using different snapshots from the Big MultiDark simulation (BigMDPL). The ray-tracing through different multiple plane has been performed with the GLAMER code accounting both for single source redshifts and for sources distributed along the cosmic time. This first paper presents weak lensing forecasts and results according to the geometry of the VIPERS-W1 and VIPERS-W4 field of view. Additional fields will be available on our data base and new ones can be run upon request. Our data base also contains some tools for lensing analysis. In this paper we present results for convergence power spectra, one point and high order weak lensing statistics useful for forecasts and for cosmological studies. Covariance matrices have also been computed for the different realizations of the W1 and W4 fields. In addition we compute also galaxy-shear and projected density contrasts for different halo masses at two lens redshift according to the CFHTLS source redshift distribution both using stacking and cross-correlation techniques, finding very good agreement. [ABSTRACT FROM AUTHOR]

ABSTRACT We investigate the ability of state-of-the-art redshift-space distortion models for the galaxy anisotropic two-point correlation function, ξ( r⊥, r∥), to recover precise and unbiased estimates of the linear growth rate of structure f, when applied to catalogues of galaxies characterized by a realistic bias relation. To this aim, we make use of a set of simulated catalogues at z = 0.1 and 1 with different luminosity thresholds, obtained by populating dark matter haloes from a large N-body simulation using halo occupation prescriptions. We examine the most recent developments in redshift-space distortion modelling, which account for non-linearities on both small and intermediate scales produced, respectively, by randomized motions in virialized structures and non-linear coupling between the density and velocity fields. We consider the possibility of including the linear component of galaxy bias as a free parameter and directly estimate the growth rate of structure f. Results are compared to those obtained using the standard dispersion model, over different ranges of scales. We find that the model of Taruya et al., the most sophisticated one considered in this analysis, provides in general the most unbiased estimates of the growth rate of structure, with systematic errors within ±4 per cent over a wide range of galaxy populations spanning luminosities between L > L* and L > 3 L*. The scale dependence of galaxy bias plays a role on recovering unbiased estimates of f when fitting quasi-non-linear scales. Its effect is particularly severe for most luminous galaxies, for which systematic effects in the modelling might be more difficult to mitigate and have to be further investigated. Finally, we also test the impact of neglecting the presence of non-negligible velocity bias with respect to mass in the galaxy catalogues. This can produce an additional systematic error of the order of 1-3 per cent depending on the redshift, comparable to the statistical errors the we aim at achieving with future high-precision surveys such as Euclid. [ABSTRACT FROM AUTHOR]